5...Nf6 6. Nc3 a6 is theoretically best - your playing the white side of a tarrasch type system:

7...Qb4 doesn't make much sense, and I don't like the development of the knight to h6, but rather to f6.

10...Qa6 might be a blunder, cxd5 wins a piece (and is also threatened for the next few turns.

13...Nfxd4 hangs a piece.

Your opponent allows you to win your piece back with 16...e4

18. Bc3 loses a piece to dxc2 followed by exf3 - same on move 19.

Bg4 is wrong see line above

b5 seeks unecessary complications - just taking e2 is probably fine.

21... Qb6? Why not Bxc5.

22... Qc7? - Bxd7

28...Qxg3+ leads to mate in one. a5?? Hangs the bishop.

I don't believe in your sacrifice after Kxf3 Rd3+ Re3.

wow thanks for the great advice.

what is it then ? lol

the french is in response to 1. e4.

your responded e6 to d4, not the french, although it may look and play in a similar fasion

Teacher: Billy, it's your turn.  Spell "bricks."

Billy: B-R-I-X.

Teacher: I'm sorry, that does not spell "bricks."

Billy: Oh yeah? Well, if you're so smart, what DOES it spell?

8... Nh6 loses the queen to 9. Nb5 and with bad play black can go an extra exchange down with moves like Nc7+

well 28.. Qxg3+ is a mate in 2

The opening ends up - after White wastes some time with c2-c3-c4 - similar to a Queen's Gambit Declined, Tarrasch Defense.

You would be better off finishing your development, especially the Ng8, before moving the Queen.  It is too early in this position to be sure where the Queen belongs, so there is a strong chance you will have to waste time moving it again.

The basic rules of opening development would help both players (scroll down the page, there are suggestions from several great players and teachers).